The present invention relates to a novel method and fastener for joining composite honeycomb panels. More particularly, a pointed fastener is provided to penetrate the internal cell structure of honeycomb construction panels without destroying the internal integrity of the honeycomb and without requiring drilling of bores through selected panels prior to insertion of the fasteners.
Existing fasteners utilized in the assembly of the T or L joints with honeycomb panels have been blunt-nosed and have required drilling bores through the first panel and the perpendicularly abutting panel before the insertion of the blunt-nosed, hollow, tubular fastener. After the fastener is in place through the predrilled bores, an adhesive or anchoring material is injected through the center of the hollow fastener and into the internal cell structure. U.S. Pat. No. 4,370,372 teaches currently utilized technologies.
With the introduction of computer numerically controlled (CNC) technology, there has arisen a need to modify the joining processes with existing honeycomb panels. CNC machines precut composite honeycomb panels and pre-drill holes or bores in the flat panel according to design standards. However, abutting panels are not predrilled. Thus, in order to join a first, flat panel with a perpendicularly abutting panel, the panels are first secured in a jig to properly align the panels for drilling (through the predrilled bore into the undrilled abutting panel) and for the insertion of the blunt-nosed fastener.
One embodiment of the present invention eliminates the necessity to pre-drill the abutting panel. A small, pointed fastener of one embodiment of the present invention provides the capability for penetrating the outer sheet member of an abutting composite honeycomb panel, passing through the internal cell structure of the abutting panel without collapsing or destroying the cell integrity in the abutting panel, and joining the predrilled flat panel with the abutting panel. It further allows for the elimination of clumsy and expensive jigs or frames for holding the panel cabinetry during fabrication.